Project Summary The long-term objectives of this proposal are: 1) to learn how molecular structure and the hydrophobic effect combine to promote the assembly of nano-capsules in aqueous solution; 2) to use this information to both gain an understanding of quaternary protein structure, and devise self-assembling nano-capsules that function as drug delivery systems. The aim of this proposal is the synthesis and analysis of water-soluble cavitands that assemble into nano-scale capsules, and in doing so entrap guest molecules within their hollow interiors. Four cavitands that differ in cavity shape and size, and the area of hydrophobic surface that promotes assembly, will be synthesized. Each can be "coated" with an external layer of functionality that modulates their assembly properties. In combination these variables engenders hundreds of homo- and hetero-capsules. Capsule formation will be examined as a function of guest to determine how they influence assembly. In addition, we will examine how the capsules kinetically stabilize normally reactive compounds. Of particular interest in this regard will be the analysis of potential anti-malarial drugs that are too unstable or insoluble to individually demonstrate activity. Analysis of the systems will be carried out with Nuclear Magnetic Resonance (NMR) spectroscopy, Isothermal Titration Calorimetry (ITC), and fluorescence spectroscopy. Relevance The development of new drug delivery systems allows new avenues for attacking disease states. In mimicry of Nature's most efficient drug delivery systems- viruses - this proposal outlines investigations into the formation and properties of nano-capsules. To date, little is known about how nano-capsules assemble in water. Hence, these studies will provide valuable information pertaining to this novel field of research.